The present invention relates to weather seals and more particularly, to the insertion and staking of a pile weatherstrip into a slotted extrusion as an on-line process.
Weather seals, particularly those having pile weatherstrips incorporating an impermeable barrier film or fin within the pile material, have excellent weathering properties. While such weatherstrips are used in various places for various sealing purposes, they are particularly suitable for sealing or weatherstripping the small clearance openings, such as between a window and a frame. These weatherstrips are particularly useful in door panels or window panels, or between the panels and the frames in which they are mounted, or between the door or window edge and an adjacent surface.
Today, plastics are increasingly being used as building materials such as, for example, window and door treatments and casings. Vinyl casings are often manufactured by extruding long, continuous lengths, which can be cut to length for customized jobs, or cut at regular intervals to make windows and door casings of standard dimensions. Typically, the vinyl lengths are extruded to specifications, and have slots throughout their length (typically configured as xe2x80x9cT-slotsxe2x80x9d or xe2x80x9cC-channelsxe2x80x9d) into which weather seals, preferably including pile weatherstrips, are inserted. The pile strip is often backed with a flexible plastic strip serving as the pile base. The configuration of the pile strip can be made to adapt to a slot of any shape. Therefore, for a T-slot, the pile strip is configured into a dimensionally matching T-shape. It is this T-shaped pile weatherstrip which must be inserted into the T-slot of a window or door casing.
Pile weatherstrip insertion has been accomplished in many ways. Pile strips have been pushed or pulled into the T-slot. The strips have also been forced into the T-slots by applying a thin-wheeled roller over the strip, which is positioned over the slot. The slotted piece being extruded is then pulled forward by the hugger roller to continuously drive the strip into the slot. See U.S. Pat. Nos. 5,103,547 and 4,528,736.
To secure the newly slotted strips in the T-slot, the strips are anchored into the extrusion slot by compressing sections of the lip of the T-slot against the base of the pile strip. This process is known as staking. A staking wheel is typically provided farther downline. See U.S. Pat. No. 5,979,036.
A staking wheel is positioned adjacent the slot rim to crimp or pin the T-slot edge into the pile strip. U.S. Pat. No. 3,295,195 shows a device which first inserts and later stakes pile weatherstrip into an aluminum extrusion.
Plastic (thermoplastic or PVC) extruded window lengths are produced faster and more economically than aluminum counterparts. It would be convenient and economically desirable to insert a pile weatherstrip into plastic window lengths as part of the plastic extrusion process. Such a process would eliminate the need for a secondary pile strip insertion process into the T-slots. However, practical problems persist.
If the pile strip is inserted on the extruding line without locking in, or staking the pile strip, it will shift within the T-slot during subsequent cutting, handling and shipping. Strips that are not staked risk xe2x80x9cdrawbackxe2x80x9d or xe2x80x9cshrink-backxe2x80x9d during the cutting process. This refers to the condition where pile weatherstrip no longer extends to provide complete coverage over the entire length of the extruded, slotted material, but xe2x80x9cdraws backxe2x80x9d due to being snagged, pulled or stretched at the cutting stage due to weak or no staking.
While wheel driven insertion and staking systems accommodate a staking frequency dictated by the extrusion line speed, the need exists for a system that can vary the staking frequency independent of the extrusion speed. The need exists for a system that can provide a variety of staking forces without degrading the extrusion. The need also exists for an assembly that can insert and simultaneously stake a plurality of weatherstrips to an extrusion. The need further exists where the plurality of inserted weatherstrips may be staked at different staking frequencies or with different staking forces to allow the selective removal of the weatherstrip for replacement or recycling purposes.
The present assembly provides for the inline insertion and staking of one or a plurality of pile weatherstrips into an extrusion travelling along an extrusion path. In addition, the present invention allows for a staking frequency and staking force independent of an extrusion line speed and the staking parameters of other pile weatherstrips.
In a first configuration, the present assembly includes a frame to which a first and a second insertion assembly are connected and operably located relative to the extrusion path to engage corresponding first and second weatherstrips with the extrusion, and a first and second staking assembly connected to the frame downstream of the first and second insertion assembly, respectively, to stake the respective first and second inserted weatherstrips to the extrusion.
In a further configuration, the present invention contemplates an insertion assembly for inserting a weatherstrip into an extrusion travelling along the extrusion path, the insertion assembly including a removable/replaceable pile channel sized to slideably receive the weatherstrip, an inlet guide upstream and spaced from the pile channel; and an insertion wheel located downstream of the pile channel outlet, the insertion wheel sized to engage the weatherstrip with the extrusion.
In a further configuration, the present invention includes a staking assembly including a translating arm moveably between an upstream position and a downstream position; and a staking pin connected to the translating arm for linear translation into and out of the extrusion path, independent of the extrusion line speed.